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Questions tagged [cidr]

Classless Inter-Domain Routing, a method for allocating TCP/IP network addresses and routing data packets. Divides IP address into network id (high bits) and host id (low bits) as determined by netmask. In 1993, replaced the older classful network routing.

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How can I check if an ip is in a network in Python?

Given an ip address (say 192.168.0.1), how do I check if it's in a network (say 192.168.0.0/24) in Python? Are there general tools in Python for ip address manipulation? Stuff like host lookups, ip adddress to int, network address with netmask to…
Staale
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Setting CIDR/IP so anyone can access it from any IP?

How do you set a CIDR/IP so anyone can access it from anywhere? I'm trying to make my AWS RDS DB instance accessible from anywhere as my ISP doesn't give me a static IP. Everytime my IP changes I have to go change the security record.
Matt
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Check whether or not a CIDR subnet contains an IP address

I'm looking for quick/simple method for matching a given IP4 dotted quad IP to a CIDR notation mask. I have a bunch of IPs I need to see if they match a range of IPs. example: $ips = array('10.2.1.100', '10.2.1.101', '10.5.1.100',…
Uberfuzzy
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Converting CIDR address to subnet mask and network address

Given a CIDR address, e.g. 192.168.10.0/24 How to determine mask length? (24) How to determine mask address? (255.255.255.0) How to determine network address? (192.168.10.0)
Dmitry
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How to see if an IP address belongs inside of a range of IPs using CIDR notation?

Here I have a static reference the ranges I need to check: private static List Ip_Range = new List() { "12.144.86.0/23", "31.201.1.176/30", "46.36.198.101/32", "46.36.198.102/31", "46.36.198.104/31", …
Only Bolivian Here
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Python 3: create a list of possible ip addresses from a CIDR notation

I have been handed the task of creating a function in python (3.1) that will take a CIDR notation and return the list of possible ip addresses. I have looked around python.org and found this: http://docs.python.org/dev/py3k/library/ipaddr.html but…
MadSc13ntist
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How can I determine an appropriate pod CIDR value for a Kubernetes cluster?

I'm initiating a kubernetes cluster with: kubeadm init --pod-network-cidr=192.168.1.0/16 --apiserver-advertise-address=192.168.0.33 I'm not too familiar with networking concepts or CIDR, how do I determine an appropriate value for the pod CIDR? I…
Chris Stryczynski
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Check if two CIDR addresses intersect?

Given two CIDR addresses say 192.168.2.0/14 and 192.168.2.0/32 How do I check if two ip addresses overlap in "python2.6"?? I have gone through netaddr and it allows to check if 192.168.2.0 is in CIDR address 192.168.2.0/14 by from netaddr import…
AjanShrestha
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Is there way to match IP with IP+CIDR straight from SELECT query?

Something like SELECT COUNT(*) AS c FROM BANS WHERE typeid=6 AND (SELECT ipaddr,cidr FROM BANS) MATCH AGAINST 'this_ip'; So you don't first fetch all records from DB and then match them one-by one. If c > 0 then were matched. BANS table: id int…
raspi
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Getting list IPs from CIDR notation in PHP

Is there a way (or function/class) to get the list of IP addresses from a CIDR notation? For example, I have 73.35.143.32/27 CIDR and want to get the list of all IP's in this notation. Any suggestions? Thank you.
TamTam
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How use netaddr to convert subnet mask to cidr in Python

How can I convert a ipv4 subnet mask to cidr notation using netaddr library? Example: 255.255.255.0 to /24
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Cidr blocks AWS explanation

Can someone explain exactly how CIDR blocks work and how it translates into 0.0.0.0/32 for example? Please use laymen’s terms or perhaps even an analogy to something not network related. Can’t seems to find an explanation that clicks with me.…
Billy
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AWS VPC Create Subnet in with different zone

I already have a VPC (Non Default) configured which is used by Amazon EC2. I need to create another subnet (Non Default) in the same VPC with a different Availability Zone. So when I am trying to Add details, I am stuck at the CIDR Block. I am…
AvtarSingh Suchariya
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Is there native .NET type for CIDR subnets?

It's simple enough to code up a class to store/validate something like 192.168.0.0/16, but I was curious if a native type for this already existed in .NET? I would imagine it would work a lot like IPAddress: CIDR subnet =…
Neil C. Obremski
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CIDR bitwise operations - could I be a bit wiser?

I am building a class to represent an IPv4 subnet. I am storing the network address and the subnet mask as 4 byte binary strings, which are built during the constructor based on the arguments. One of the representations I would like the constructor…
DaveRandom
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